A Tale of Three Invasive Insect Pests: Exploring Control Mechanisms for the Potato Psyllid (Bactericera cockerelli), the Rice Water Weevil (Lissorhoptrus oryzophilus), and the Rice Delphacid (Tagosodes orizicolus)

Abstract

The occurrence of invasive insect pests has increased as temperatures and trade increase globally. Invasive pests are spread from large countries like the United States and are spread to these large countries. Invasive insect pests can cause devastating yield losses in agricultural fields. Therefore, it is imperative to study them and develop science-based methods for their management. Bactericera cockerelli, the potato psyllid, and Lissorhoptrus oryzophilus, the rice water weevil, are two insect pests that are native to the US but invasive elsewhere. The potato psyllid is invasive in New Zealand, Australia, and Ecuador, and the rice water weevil is invasive in several Asian and European countries. One insect pest that is invasive to the US is Tagosodes orizicolus, the rice delphacid, a pest of rice and vector of Rice hoja blanca virus is native to the tropical Americas and invasive to the US. These three insects are major pests of agriculture, whether of solanaceous crops, such as the potato psyllid, or of rice, as the rice water weevil and the rice delphacid. In this dissertation I assessed integrated pest management technologies for all three insect pests. For the potato psyllid, I identified an electron beam irradiation dose to prevent development and reproduction of adult psyllids on plant cuttings that are shipped internationally. For the rice water weevil, I identified rice varieties that display field resistance to the pest. For the rice delphacid, I showed that individuals collected in Texas do not carry Rice hoja blanca virus and identified the salivary glands in nonviruliferous insects as a likely barrier for the virus’s transmission. Altogether, this dissertation expanded our knowledge on these three important agricultural pests by evaluating control mechanisms for the potato psyllid and rice water weevil and increasing our understanding on the newly invasive rice delphacid.